Complex quaternary ammonium compounds



Patented Oct. 10, 1944 UNITED STATES PATENT orrlce COMPLEX QUATERNARYAlVIMIONIUM COMPOUNDS John M. Tinker, Penns Grove, N. J., and Adrian L.Linch, Wilmington, Del., assignors to E. I. du Pont de Nemours a;Company, Wilmington, Del .,-a corporation of Delaware No Drawing.Application January 11, 1943,

- Serial No. 472,000

7 Claims. (Cl. 260-482) may be used in place of or in admixture withsoap and the numerous soap substitutes heretofore described in theliterature. Additional ob- J'ects will become apparent from aconsideration of the followed description and claims.

These objects are attained in accordance with the present inventionwherein a halogenated aliphatic carboxylic acid ester and atrialkylamine are reacted at temperatures below about 35 0., thereaction being continued for a sufficient period of time to permit afurther reaction between the quaternary ammonium compounds initiallyproduced. In a more restricted sense this invention is concerned with aprocess wherein an alpha-halogeno-aliphatic carboxylic acid ester isreacted with a tn'alkylamine at temperatures with-' in the range ofabout C. to about 35 C., the reactants being maintained in contact witheach other under the foregoing conditions for a sufiicient period oftime to permit a further reaction between the quaternary ammoniumcompounds initially produced. In a still more restricted sense thisinvention is directed to a process wherein esters ofalpha-bromo-aliphatlc carboxylic acids, which acids contain at least sixcarbon atoms, are condensed at room temperatures with low molecularweight trialkylamines in the presence of a polar solvent, the reactionbeing continued for a sufiicient period of time to permit a furtherreaction between the quaternary ammonium compounds initially produced.In its preferred embodiment the invention is directed to the reaction atapproximately room temperature of an ester of an alpha-bromo-aliphaticcarboxylic acid,

which acid contains from twelve to eighteen carbon atoms, withtrimethylamine in the presence of a polar solvent such as methylalcohol, the reactants being maintained in contact with each other underthe foregoing conditions for a sufficient period of time to permitfurther reaction be tween the quaternary ammonium compounds in.- itiallyproduced. Theinventlon is also concerned with products produced inaccordance with the foregoing or equivalent processes. An additionalcomplex quaternary ammonium compounds to methyl ammonium bromide.

diluted with 440 parts of benzene and 260 parts feature of the inventionis the conversion of these derivatives thereof. Another feature is theemployment of the foregoing and related products in the industrial artsand particularly in the soap substitute field.

The invention may be more readily understood by a consideration of thefollowing illustrative examples wherein the quantities are stated inparts by weight.

In these examples an equation is given for the reaction which probablyoccurs, although it is to be understood that the invention is not to berestricted to the reactions set forth in these equations.

precipitated tetramethyl ammonium bromide, the

filtrate was evaporated to a small volume by heating at -80 C. underreduced pressure. Sixty parts of dry acetone was added, the mixturechilled for several hours and filtered from tetra- Ihe filtrate was ofsolvent distilled out of the mixture to remove traces of water andtrimethylamine. The residue on cooling deposited crystals, which werefiltered off and crystallized from parts of dry acetone. The crystalsmelted at 113-115 C. Further crystalllzation from dry acetone raised themelting point to 1313-13? C.

176 parts of trimethylamine and 107 parts of methyl-alpha-bromo-capratewere dissolved in 300 parts of methyl alcohol. After agitating forAnalysis I Found Theory Percent nltro- 5.03 5.08 (M. W. 553) GnHuO N BrPe fc entbromine 14.58 14.52 Melting ran gsu (H50 From the filtratesfrom the preceding crys tallizations, further quantities of the sameproduct may be obtained.

Exluurpn III 2CH;(OH2)1aOHBr-COOCHz+3N(CHa)s (CHahNBr-i- 0 (CH1): COOCH:GHa(CHz)n-CHCON-C (CHOENBI mrCHl 175 parts ofmethyl-alpha-bromo-palmitate was added to a solution of 220 parts oftrimethylamine dissolved in 375 parts of anhydrous methyl alcohol. Themixture was agitated at 20-25 C. for 185 hours and then filtered toremove tetramethyl ammonium bromide, which crystallized during thereaction. The mother liquors were chilled and filtered from whitecrystals melting at 1691'l3 C. After crystallization from a mixture of158 parts of dry acetone and 20 parts of absolute methyl alcohol, theymelted at 180-183 C.

Analysis Found Theory (M. W. 408) for- Per cent nitrogen 3.40 3.45CH3-(CHzhr-CH-COOCH; Per cent bromine 19. 64 19. 65 (CH|)ENB1'Additional product of the above constitution was obtained by working upthe filtrates. The mother liquor from the above recovery was dilutedwith 440 parts of benzene, and 260 parts of solvent was distilled oil toremove traces of water. Crystals which separated on cooling werefiltered off and washed with dry, cold acetone. The product wascrystallized from a mixture of 240 parts of acetone and 24 parts ofmethyl alcohol.

Analysis I Found Theory Per cent nitrogen 3. 78 3. 88 OnHuOANiBI. Percent bromine 11. 8 11. 1 M. R degrees.. 146-1 Additional product may beobtained from the mother liquors.

Similar results were obtained with methyl esters ofalpha-bromo-stearic-, alpha-bromolauricand alpha-bromo-capric-acids. Thealpha-chloro and alpha-iodo derivatives. likewise produce analogousproducts.

These ester derivatives are saponified by alkaline reagents. Thus thederivative from methylalpha-bromo-palmitate was saponlfied by boiling in0.3 normal sodium hydroxide solution for 14 hours. The sodium saltrecovered by evaporation and crystallization from acetone and methylalcohol mixture melted at 190-193 C. and contained one-half atom ofbromine per atom of nitrogen.

22 parts of n-octyl-alpha-bromo-caprylate and a solution of 29 parts oftrimethylamine dissolved in 52 parts of absolute methyl alcohol wereagitated at room temperature (23-28" C.) for nine days. The mixture waschilled and filtered from tetramethyl ammonium bromide. The motherliquors were evaporated under reduced pressure, diluted with parts dryacetone, chilled and an additional quantity of tetramethyl ammoniumbromide filtered off. The filtrate was evaporated to dryness underreduced pressure, treated with 80 parts of petroleum ether, chilled,filtered and the product crystallized from a mixture of acetone andpetroleum ether.

Analysis COOCH;

Theory (M. W.=290) for Nitrogen M. C

The filtrate was evaporated under reduced pressure, and extracted with300 parts of water. The extract was washed with '70 parts of ether, andevaporated under reduced pressure at BEE-40 C. 350 parts of benzene wasadded and traces of water removed by distillation at -140 mm. pressureand at 50 C. The crude product was crystallized from a mixture of etherand acetone and was identical with the product described in Example I.

Similar results are obtained by carrying out the reaction in ethyl,propyl, butyl and amyl alcohols to obtain the corresponding estercomplexes by ester interchange during the reaction with trimethylamine.Other esters, for example propyl, amyl, hexyl, dodecyl, octadecyl,phenyl, cyclohexyl, etc., of alpha-bromo-aliphatic acids from butyric tomontanic and higher acids undergo ester interchange when condensed withtrimethylamine in an alcohol of different molecular weight than presentin the original ester. It is obvious that by employing the same alcoholfor solvent and esterification the corresponding ester group will bepresent in the final condensation product.

EXAMPLE V (CH3): C O O CH: omomm-on-oomon oedema-onion (CHa)aENBr OYCHZMBCHS (CH3): COO(CH2)3CH:

CHa(OH2)nCH-CONCH 0530B (oHoENBr (CHzMs-CH;

60 parts of anhydrous n-butyl alcohol (B. P. 118 0.), 5 parts of theproduct described in Example III, and 0.05 part of lead oxide (litharge)were heated together at 60-65 C. for 3 hours. The pressure was reducedto '75-'78 mm. and the methyl alcohol and excess butyl alcohol distilledoff. The-residue was twice crystallized from dry acetone and melted at152-154.

This ester interchange reaction may be applied to the synthesis of avariety of esters by employing other alcohols in place of n-butylalcohol. Likewise, the products described in Examples I and II or otheresters thereof may be employed as starting materials in this esterinterchange with higher molecular weight alcohols.

It is to be understood that the foregoing example are representativemerely of a relatively few of the many embodiments of this invention.They may be varied widely with respect to the individual reactants, theamounts thereofand the conditions of reaction without departing from thescope hereof.

In place of or in addition to the halogenated aliphatic carboxylic acidesters referred to in the foregoing examples, numerous other com-'pounds may be employed. .These compounds are preferably esters ofaliphatic carboxylic acids which acids contain six or more carbon atomsand advisably from twelve to eighteen carbon atoms. Esterification ofsuch acids may be accomplished in accordance with well known procedureby treatment with various alcohols, either monohydric or polyhydric. Thehydrocarbon radical of such alcohols is preferably, but not necessarily,an alkyl group of no more than twenty carbon atoms, although it may becycloaliphatic and/or may contain alkoxy and/or halogen groups. Theforegoing esters have substituted thereon a halogen atom which may be Ichlorine, bromine or iodine. Substitution may take place in variouspositions although for optimum results it is advisable that it be in thealpha position.

The hydrocarbon group of the foregoing acids and alcohols may bestraight or branch chain and may contain one or more additionalsubstituents which do not enter into or interfere with the reactiondescribed herein.

The foregoing esters are reacted with a trialkylamine which ispreferably of low molecular weight. Numerous well known trialkylamines,either alone or in admixture with one another, may be used for thispurpose. Likewise, these amines may be further substituted provided thatthe substituent or substituents does not react with or interfere withthe described reaction. A representative few of such amines are ethyldimethylamine, hydroxy ethyl dimethylamine,di(hydroxy-ethyl)-methylamine and triethanolamine.

i The foregoing reaction is advisably carried out in a polar solventsuch as methyl alcohol, ethyl alcohol, water, etc.

As previously mentioned, one or more aliphatic acid esters and one ormore trialkylamines may be employed to produce compounds of .the desiredcharacter. The amounts of the'individual reactants may vary widelyalthough it is generally preferable to use a large excess of thetrialkylamine. In the case of the solvent employed, the amount may varywidely but it is advisable to use sufiicient thereof in order that thereaction mixture maybe kept in a fluid state.

To produce the products described herein it is essential that thetemperature of the reaction shall be kept below about 35 C. Temperaturesof from about 0 C. to about 35 C. are satisfactory and for mosteconomical results temperatures approximating room condition should beemployed. Temperatures above about 35 C. should not be used since theywill prevent formation of the desired complex quaternary ammoniumcompounds. Temperatures below 0 C. are

suitable but they usually require an excessive period of time to producethe desired results and for that reason, a well as the cost, are notfully recommended,

Itis important that not only should the temperature be maintained withinthe foregoing rang but'sufficient time should be allowed to permit theinitially formed quaternary ammonium compounds to react and producecomplex derivatives of higher molecular weight. These derivativesgenerally contain two pentavalent nitrogen groups but they may be evenmore complex and contain three or more of such groups, depending uponthe reactants, the temperature, and the time of reaction. In any event,they should contain no less than two pentavalent nitrogen atoms and forthis reason the instructions previously given, particularly with respectto temperature and time, should be carefully followed.

Complex quaternary ammonium compounds produced in accordance with theinstructions hereof may be further modified by condensation with primaryor secondary aliphatic or aromatic amines to yield amide-like quaternaryammonium complexes. Amides of this type are likewise of considerablevalue in the industrial arts and for the most part exhibit unusual andvaluable surface-active properties.

The products .of this invention are characterized by excellentsurface-active properties in aqueous solution. They are particularlygood detergents in neutral, acid or alkaline mediums and in the presenceof alkaline earth and heavy metal salts. In addition, these productsgive outstanding results as electroplating assistants, reduction ofanti-freeze surface tension, foam promoters, dyeing assistants, vat dyeretardants, leveling agents in dye baths, printing assistants, woolscouring agents, flotation assistants, wetting agents, emulsifyingagents, dispersing agents for dyes, latex, clay, pigments, etc.,softening and swelling agents for synthetic fibers, boiling offassistants for rayons, corrosion inhibitors and assistants in acidpickling baths, leather tanning assistants, etc.

As many widely different embodiments of this invention may be madewithout departing from the spirit and scope thereof, it is to beunderstood that the invention is not limited to, the specificembodiments thereof'except as defined in the appended claims.

We claim:

1. A process which comprises mixing at temperatures within the range ofabout 0 C. to about 35 C. approximately two molar quantities of an alkylester of an alpha halogeno aliphatic carboxylic acid, said acidcontaining from six toeighteen carbon atoms, and approximately threemolar quantities of trimethylamine in the presence of a polar solvent,said reaction being continued for a suflicient period of time to permita further reaction between the quaternary ammonium compounds initiallyproduced, then separating the excess trimethylamine from the resultingproduct.

' 2. A process which comprises mixing at approximately room temperatureapproximately bromo aliphatic carboxylic acid, said acid containing-fromsix to eighteen carbon atoms, and approximately three molar quantitiesof trimethylamine in the presence of a polar solvent, said reactionbeing continued for a suilicient period of time to permit a furtherreaction between the quaternary ammonium compounds initially produced,then separating the excess trimethylamine from the resulting product.

3. A process which comprises miin'ng at approximately room temperature.approximately two molar quantities of an alkyl ester of an alpha bromoaliphatic carboxylic acid, said acid con-' taining from twelve toeighteen carbon atoms, and approximately three molar quantities oftrimethylamine in the presence of methyl alcohol, said reaction beingcontinued for a sufflcient period of time to permit a further reactionbetween th quaternary ammonium compounds initially Produced, thenseparating the excess trimethylamine from the resulting product.

4. A process which comprises condensing at approximately roomtemperature approximately two molar quantities of methylalpha-bromopalmitate and approximately three molar quantitles oftrimethylamine in the presence of methyl alcohol, said reaction beingcontinued for a, suflicient period of time to permit a further reactionbetween the quaternary ammonium compounds initially produced, thenseparating the excess trimethylamlne from the resulting product.

5. Quaternary ammonium compounds represented by the following-formula:

wherein R represents an alkyl group of four to sixteen carbon atoms, R1represents an alkyl group, and X represents a member selected from theclass consisting of chlorine and bromine groups.

6. The quaternary ammonium compounds of I (CHQEN JOHN M. TINKER. ADRIANL. LINCH.

